1. Field of the Invention
The present invention relates to a library apparatus for containing a magnetic tape cartridge or the like and a hand mechanism used in the library apparatus.
2. Description of the Related Art
A magnetic tape library apparatus includes: an entry/exit mechanism wherein a plurality of cells (container chambers) are superimposed on one another in the vertical direction like a book shelf; and a hand mechanism for taking out a cartridge from a cell. When an operator puts a cartridge into the entry/exit mechanism (container shelf), the cartridge is detected and moved from entry/exit mechanism to a predetermined position by the hand mechanism.
In the conventional magnetic tape library apparatus, the cartridge is detected as follows.
The hand mechanism for carrying the cartridge includes a picker unit for grasping and taking out a cartridge in the entry/exit mechanism. The picker unit has a sensor for detecting presence/absence of a cartridge in a cell.
Firstly, the hand mechanism moves to be positioned at a cell (container chamber) where the entry/exit mechanism is found. After this, the sensor detects presence/absence of a cartridge. If a cartridge is present, the cartridge is grasped by the picker unit. If no cartridge is present, the hand mechanism moves to be positioned at the next stage and detects presence/absence of a cartridge.
In this conventional method, in order to detect a cartridge contained in the entry/exit mechanism, the hand mechanism should be positioned at each of the cells to detect presence/absence of a cartridge. That is, the hand mechanism should stop its movement when positioned for a cartridge. This slows down the cartridge detection speed.
Moreover, Japanese Patent Publication No. 09-002612 discloses a cartridge detection method, wherein all the cartridges are provided with a light source and the hand mechanism includes a light reception unit as a sensor, so that a cartridge is detected by receiving the light; or wherein a reflection plate is attached to the end surface of each of the cells and the hand mechanism has a light receiving unit for applying light to the reflection plate and receiving reflected light, so that reflection can decide that no cartridge is contained.
However, this method has a problem of costs for providing a light source on all the cartridges or reflection plates in all the cells.
It is therefore an object of the present invention to provide a hand mechanism and library apparatus that can perform a high-speed cartridge detection and that can be produced at a reduced cost.
The hand mechanism according to the present invention is for fetching a cartridge contained in a plurality of container chambers provided on a container shelf in a library apparatus, the hand mechanism comprising:
a picker unit for taking out a cartridge; and
cartridge detector for applying a detection light in a direction intersecting the cartridge taking out direction and receiving a reflected light.
In this hand mechanism, the detection light is applied in a direction intersecting the cartridge taking out direction. Accordingly, the detection light can be applied simultaneously to a plurality of container chambers.
For example, in FIG. 1, the detection light from the cartridge detector 21 is shown by an alternate long and short dash line. As can be seen from FIG. 1, the detection light intersects the cartridge taking out direction, i.e., the opening direction of the container chambers. The detection light is simultaneously applied to both of the container chamber 13-1 and the container chamber 13-2.
And, for example, a reflection plate 14 is provided in the container chambers for reflecting the detection light in the direction of the detection light. If at least one of the container chambers 13-1 and 13-2 contains a cartridge, no reflection light is received. That is, in the state of FIG. 1, a cartridge is contained in two of the container chambers, the detection light is cut off and no reflection light is generated.
That is, if no reflection light is received, it is found that at least one of the container chambers contains a cartridge, and if reflection light is received, it is found that none of the container chamber contains a cartridge.
The library apparatus according to the present invention comprises: a container shelf including a plurality of container chambers for containing a cartridge; and a hand mechanism for taking out the cartridge contained in the container shelf, wherein the container chambers have reflector, and the hand mechanism includes: a picker unit for taking out the cartridge, and cartridge detector for applying a detection light in a direction intersecting the cartridge taking out direction and receiving a reflected light from the reflector, wherein the detection light is applied over two or more container chambers at once.
In this library apparatus, a detection light is applied to a plurality of container chambers at once. If one of the container chambers contains a cartridge, the detection light is cut off, not reaching the reflector, and no reflection light is received. That is, if no reflection light is received, it is found that at least one of the container chambers contains a cartridge, and if a reflection light is received, it is found that none of the container chambers contains a cartridge.